Production of aromatic nitriles



Patented Oct. s, 1948 UNITED STATES PATENT OFFICE PRODUCTION or AROMATICMilton M. Marisic, Northfleld, 111., and

1. Benton, Woodbury, and Richard BJBIshop; Haddonfleld, N. J assignorsto socon'yevacuum Oil Company, Incorporated, a corporation New York NoDrawing. Application October 29, 1946, Serial No. 706.516

11 Claims. 01. 260-465) valuable products such as acids, amines,aldehydes, esters, etc.'

As is well known to those familiar with the art,

several processes have been proposed for the preparation of aromaticnitrlles. In general, however, all of these processes have beendisadvantageorus from one or more standpoints, namely, the relativelyhigh cost of the reactants employed and/or the toxic nature of some ofthe reactants and/or the number of operations involved in their ultimatepreparation. For example, aromatic nitriles have been synthesized byreacting alkali cyanides with aromatic sulfonates or witharomatic-substituted alkyl halides; by reacting more complex cyanidessuch as potassium ouprous cyanide, with diazonium halides; by reactingisothiocyanates with copper or with zinc dust; and by reacting arylaldoximes with acy-l halides.

We have now found a process for producing aromatic nitriles which issimple and inexpensive, and which employs non-toxic reactants.

We have discovered that aromatic nl'triles can be prepared by reactingaromatic hydrocarbons having at least one nuclear hydrogen atom replacedby a unlvaient aliphatic hydrocarbon radical, with ammonia at elevatedtemperatures, in the praence of certain catalysts of the type definedhereinafter.

Our invention is to be distinguished from the conventional processes forthe production of hydrogen cyanide wherein carbon compounds, such ascarbon monoxide, methane, and benzene. are reacted with ammonia atelevated temperatures in the presence oi alumina, nickel, quartz, clays,oxides of thorium and cerium, copper. iron oxide, silver, iron, cobalt,chromium, aluminum phosphate, etc. The process of the present inventionis abo to be distinguished from the processes of the prior art for theproduction of amines when? in hydrocarbons are reacted with ammonia athigh temperatures, or at lower temperatues in the presence of nickel.

Accordingly, it is an object of the present invention to provide aprocess for the production of aromatic nitriles. Another object is toafford a catalytic process for the production of aromatic nitriles. Animportant object is to provide a proc ess for producing aromaticnitriles which is inexpensive and commercially feasible. A specific zobject is to provide a process for producing aromatic ni-triles fromaromatic hydrocarbons having at least one nuclear hydrogen atom replacedby a univalent aliphaticw hydrocarbon radical.

Other objects and advantages of the present in- 3 vention will becomeapparent .to those skilled in the art from the following dmcription.

Broadly stated. our invention provides an inexpensive and commerciallyfeasible process for the production of aromatic nitrilcs; whichcomprises reacting an aromatic hydrocarbon having at least one nuclearhydrogen atom replaced by a univalent aliphatic hydrocarbon radical,with ammonia, in the gaseous phase and at elevated temperatures, in thepresence of catalytic material obtained by decomposing a heteropoly acidor a salt of a heteropoly acid, containing an element selected from thegroup consisting of molybdenum, tungsten and vanadium.

Generally speaking, any aromatic hydrocarbon 1 having at least onenuclear hydrogen atom replaced by a univalent aliphatic hydrocarbonradical is suitable as the hydrocarbon reactant in the process, of ourinvention. The aromatic hydrowrbons to be used in the process of ourinvention may bederived from any suitablesource as is well known tothosefamiliar with the art. Although any aromatic hydrocarbon having atleast one nuclear hydrogen atom replaced by a univalent aliphatichydrocarbon radical may be employed for our purpose, weprefer to use themethyl-substituted aromatic hydrocarbons, or those in which thealiphatic hydrocarbon radical suibstituent or at least one of thealiphatic hydrocarbon radical substituentszis unsaturated; moreparticularly, the thus substituted benzenes. Examples are toluene,-xylenes. trimethyl benzenes, and styrene. Itls to be understood.however, that hydlocarbonfractions containing benzenes having at leastone miclear hydrogen atom replaced by a univalent-aliphatic hydrocarbonradical may also be utilized-incur. process. It is to be understoodalso, that other aromatic hydrocarbons having at least one nuclearhydrogen atom replaced by a aliphatic hydrocarbon -radlcal, such as. metyl-substituted naphthalenes, and fractions containing the same may beemployed in the presentprocess.

The proportlonsof reactants, i. e., aromatic hydrocarbon having at leastone nuclear hydrogen atom replaced by a univalent aliphatic hydrocarbonradical and ammonia, used in our process may be varied over a wide rangewith little eiiiect on the conversion per pass and ultimate yield. Ingeneral, the charge of reactants may contain as little as 2 mol. percentor as much as 98 mol. percent of aromatic hydrocarbons. In practice,however, we use charges containing between about 20 mol. percent andabout .90 mol, percent of am matic hydrocarbon, and ordinarily, weprefer to use charges containing a molar excess of cmmonia over thearomatic hydrocarbon reactant.

As stated hereinbefore, we have found that the catalysts to be used toproduce aromatic nitriles by reacting aromatic hydrocarbons having atleast one nuclear hydrogen atom replaced by a univalent aliphatichydrocarbon radical, with ammonia are those obtained by decomposingthermally heteropoly acids and salts of heteropoly acids, containing anelement selected from the group consisting of molybdenum. tungsten, andvanadium. r

Heteropoly acids are well known in the literature (Modern Aspects ofInorganic Chemistry, H. J. Emelus and J. S. Anderson; New York; 1940;chapter V) The heteropoly acids operative in the process of the presentinvention are those which contain an acid anhydrlde'molecule selectedfrom the group consisting of Moos, W; and V205, and at least one otheracid anhydride-type molecule. the latter being regarded as the centralgroup of the acid. These heteropoly acids may also be defined broadly asthose acids formed by the union of a radical of molybdic, tungstic orvanadic acidsor two or more of these radicals-with one or more radicalsof other fairly strong acids or with amphoteric metal hydroxides. Atypical heteropoly acid is phosphomolybdic acid, i. e.,IIJIPO1(MOO3)I2].IH20, in which :n represents the number of molecules ofwater associated with the crystalline acid and is generally a wholenumber, live to twenty-nine, wherein the phosphate group (P04) is thecentral group. Other representative acids which may be mentioned by wayof non-limiting examples, are silico-molybdic acid, i. e., HdSlOKMOOaha].rI-IaO, and phosphovanadotungstic acid, i. e.,

H3[PO4(V2O5) 2(W0s) alJHzO Salts of the heteropoly acids referred to.which also are well known in the art, are likewise suitable for thepreparation of the catalysts of the process of the present invention.Typical salts of the-heteropoly acids are ammonium silicomoiybdate, i.e., (NH4)4[SiO4(MOOs)i2].$H2O, and nickel silicomolybdate, i.-e.,

NlzESlOdMOOa) uLXHzO These are mentioned by way of non-limitingexamples.

In the interest of brevity, the heteropoly acids and the salts ofheteropoly acids contemplated herein as parent materials orintermediates of the catalystaoperative in the present process will bereferred to hereinafter and in the claims, individualiy. as a class, andcollectively, as heteropoly compounds. The heteropoly compounds may beprepared by any of the methods disclosed in the literature.Advantageously, the components of a heteropoly compound may becomposited, blended, or mixed by any suitable means to form an intimatemixture without preparing the heteropoly compound directly, and yet manyof the benefits of catalysts prepared from an intermediate heteropolycompound are obtained.

Accordingly, the catalytic materials of the present invention may beobtained by thermally decomposing a heteropoly compound, i. e., aheteropoly acid or a salt of a heteropoly acid. under the hereinafterdefined conditions. In general, the temperatures to be used foreffecting the thermal decomposition of the heteropoly compounds dependupon the period of time during which a heteropoly compound is subjectedto a given temperature. The object of the th maltreatment of theheteropoly compounds is to dehydrate and to decompose them to producecatalytic oxides and yet avoid unnecessary sintering of the resultantcatalytic oxides. Sintering detracts from the catalytic activity of theresultant catalytic oxides by reducing the surface area thereof.Accordingly, to obtain the most active catalysts, the thermal treatmentof the heteropoly compounds must be carried out at a temperature and fora period of time suflicient to decompose a heteropoly compound, whilemaintaining sintering of the resultant catalytic oxides to a minimum. Inpractice, we have found that treatment of the heteropoly compounds attemperatures varying between about 300 F. and about 950 F.. for periodsof time varying between about two hours and about ten hours, are mostconvenient from the standpoint of com- .mercial manufacture of thecatalysts to be used in the process of this invention. It must beclearly understood, however, that higher or lower temperatures may beused, provided that at higher temperatures, relatively short periods oitime are employed so that sintering of the resultant catalytic oxides iskept at a minimum, and that at lower temperatures, relatively longerperiods of time are employed to ensure decomposition of the heteropolycompounds.

While the decomposition products of the heteropoly compounds exhibit anappreciable degree of catalytic effectiveness when used per so. theygenerally possess additional activity when used in conjunction with thewell known catalyst supports, such as activated alumina, bauxite,

silica gel, carborundum, pumice, clays, and the like. Weespeciallyprefer to use activated alumina (A1203) as a catalyst support. Withoutany intent of limiting the scope of the present invention, it issuspected that the enhanced catalytic activity of the supportedcatalysts is attributable primarily to their relatively large surfacearea.

The concentration of catalytic heteropoly compound in the supportedcatalysts influences the conversion per pass. In general, the conversionper pass increases with increase in the concentration of heteropolycompound. For example, we have found that a catalyst comprisinginitially 20 parts by weight of phosphomolybdic acid on parts by weightof activated alumina is more effective than one comprising initially 10parts by weight of phosphomolybdic acid on parts by weight of activatedalumina. It is to be understood, however, that supported catalysts con--taining larger or smaller amounts of catalytic heteropoly compound maybe used in our process.

The catalysts of the present invention possess several advantages. Inaddition to providing relatively high conversions of aromatichydrocarbons having at least one nuclear hydrogen atom replaced by aunivalent aliphatic hydrocarbon radical into 'aromatic nitriles, theyare readily regenerated without loss thereof. In operation, thecatalysts become fouled with carbonaceous material which ultimatelyaffects their catalyticactivity. Accordingly, when the efficiency of thecatalyst declines to a point where further operation becomesuneconomical or disadvantageous from a practical standpoint, thecatalyst may be regenerated as is well known in the art, by subjectingthe same to a careful oxidation treatment, for example, by passing astream of air or air diluted with flue gases over the catalyst underappropriate temperature conditions and for a suitable period of time,such as the same period oftime as the catalytic operation. Preferably,the oxidation treatment is followed by a purging treatment, such aspassing over the catalyst a stream of purge gas, for example, nitrogen.carbon dioxide. steam, etc.

The lower oxides of the aforesaid heteropoly compounds, obtained bydecomposing thermally the latter, are not volatile under conditionsgenerally employed in oxidative catalyst regeneration. Therefore, itwill be apparent that these catalysts will have a long useful life. Thevolatility of the catalysts used herein can be correlated with theircolor. Thus, phosphomolybdic acid (or ammonium phosphomolybdate) ondecomposition yields a product which is dark blue in color andnon-volatile; whereas arsenomolybdic acid decomposes to a product whichis faint blue in color and which is slightly volatile at elevatedtemperatures in a current of air. Decomposition of silico-molybdic acidresults in a product which is intermediate in color and volatility tothose of the catalytic products obtained from phosphomolybdic acid andarsenomolybdic acid.

Illustrative of the catalysts contemplated for use in the process of thepresent invention are the following:

EXAMPLE 1 Decomposition product of phosphomolybdic acid on activatedalumina Two hundred (200) c. c. of 36% hydrochloric acid were added to600 c. c. of a solution containing 400 grams of sodium molybdate,

with constant stirring. The resulting solution was maintained at atemperature of 170 F. and 400 c. c. of a solution containing 98.6 gramsof sodium monohydrogen phosphate,

NaaHPOclZHzO were added thereto, followed by 422 c. c. of 38%hydrochloric acid, the latter being added dropwise while the solutionwas constantly stirred. The yellow colored solution thus formed wascooled to room temperature (about 70-75 F.) and extracted with diethylether. The ether-phosphomolybdic acid complex so formed was then dilutedwith distilled water and poured onto 500 c. c. of activated alumina(8-14 mesh granules). Ether and water were removed by evaporation andthe impregnated alumina thus formed was gradually heated to atemperature of 840 F. and maintained at that temperature for two hours.The catalytic material thus obtained was dark blue in color andcomprised oxides of molybdenum and phosphorus on alumina? Exams: 2

Decomposition product of ammonium phosphovanadotungstate on activatedalumina Two hundred (200) grams of ammonium tungstate, (NH4)IWO4, 43.4grams of ammonium metavanadate. NHAVO'J, 8.6 grams of ammoniummonohydrogen phosphate. (NHdzHPOr, and 140 c. c. of 36% aqueous ammoniawere added to 3 liters of distilled water. The mixture was stirred andheated to a temperature of about 200 F. until solution of the salts wascomplete. The volume was kept constant by occasionally adding distilledwater. A deep red Solution was obtained. The solution was evaporated toabout 500 c. c. and then was poured onto 500 c. c. of activated alumina(8-14 mesh granules). Water was removed by evaporation and theimpregnated- Exams: 3

Decomposition product of silicomolybdic acid on activated alumina Thiscatalytic material was prepared in the same manner as the catalyst ofExample 1, with the exception that the sodium monohydrogen phosphate wasreplaced by sodium silicate. The catalyst thus obtained was pale blue incolor and comprised the oxides of molybdenum and silica on alumina.

The reaction or contact time, i. e., the period of time during which aunit volume oi the reactants is in contact with a unit volume of catalyst, may vary between a fraction of a second and several minutes. Thus.the contact time may be as low as 0.01 second and as high as 20 minutes.We prefer to use contact times varying between 0.1 second and oneminute, particularly, between 0.3 second and 30 seconds. It must berealized that these figures are at best estimates based on a number ofassumptions. For all practical purposes, as in catalytic processes ofthe type of the present invention, the more reliable data on contacttime is best expressed. as is well known in the art, in terms of liquidspace velocities, in the present instance. the volume of liquidhydrocarbon reactant per volume oi catalyst per hour. For example. atatmospheric pressure, we have found that the space velocities may bevaried considerably and that velocities varying between about one-fourthand about 4 are quite satisfactory for'the purpose of the presentinvention.

In general, the temperatures to be used in our process vary betweenabout 850 F. and up to the decomposition temperature of ammonia (about1250-1300' F), and preferably, between about 925 F. and about 1075" F.The preferred ternperature to be used in any particular operation;-

will depend upon the nature of hydrocarbomresactant used and upon thetype of catalyst employed. Generally speaking, the higher temperaturesincrease the conversion per pass but they also increase thedecomposition of the reactants thereby decreasing the ultimate yields ofaromatic nitriles. Accordingly, the criteria for determining the optimumtemperature to be used in any particular operation will be based on thenature of the hydrocarbon reactant. the type of catalyst, and aconsideration of commercial feasibility from the standpoint of strikinga practical balance between conversion per pass and losses todecomposition.

The process of the present invention may be carried out atsubatmospheric, atmospheric or superatmospheric pressures.Superatmospher'ic pressures are advantageous in that the unreactedcharge materials condense more readily. Subatmospheric pressures appearto favor the reactions involved since the reaction products have alarger volume than the reactants. and hence. it is evident from the lawof Le Chatelier-Braun that the equilibrium favors nitrile formation moreat reduced pressures. However, such pressures reduce the throughput ofthe reactants and present increased difllculties in recycling unreactedcharge materials. Therefore. atmospheric pressure or superatmospherlcpressures are preferred.

At the present time, the reaction mechanism 8 separated from theunchanged toluene by any of the numerous and well known separationprocedures, such as fractional distillation. Similarly. the uncondensedhydrogen and unchanged aminvolved in the process of the presentinvention rncnia can be separated from each other. The is not fullyunderstood. Fundamentally, the unchanged toluene and ammonia can berecycled, simplest possible method of making aromatic with or withoutfresh toluene and ammonia. to nitriles is to introduce nitrogen directlyinto the the process. aliphatic hydrocarbon radical of the aromatic Itwill be apparent that the process may be hydrocarbon reactant molecule,thereby avoid- 10 operated as a batch or discontinuous process es mi:intermediate steps with their accompanying by using a catalyst-bed-typereaction chamber increased cost. In our process, we have noted in whichthe catalytic and regeneration operathat considerable amounts 0!hydrogen are tions alternate. With a series of such reaction evolved;hence. it is postulated, without any inchambers, it will be seen that asthe cata y ic tent of limiting the scope of the present inveninoperation is taking place in one or more of the tion, that the aromaticnitriles are formed in acreaction chambers, regeneration of the catalystcordance with the following equations, using will be taking place in oneor more of the other toluene, xylene and mesitylene as examples:reaction chambers. CorrespondingLv, the process 1 may be continuous whenwe use one or more cata- CH: ON lyst chambers through which the catalystflows U an. O 3H- in contact with the reactants. In such a continuousprocess, the catalyst will flow through the reaction zone in contactwith the reactants 1 and will thereafter be separated from the reac--0Hi tion mixture, as or example, by accumulating NH 311: the same on asuitable filter medium. before con- CH3 densing the reaction mixture. Ina continuous process, therefore, the catalyst-fresh or regen- 1 on, on.erated-and the reactantsiresh or recycle will continuously flow througha reaction chamr ber. me on m0 0N am The following detailed examples arefor the purpose of illustrating modes of preparing aroma b can-ted out bmam matic nitriles in' accordance with the process oi 1 2 z igg fiiz ikn w t h g g for our invention, it being clearly understood that theoperating catalytic reactions in the vapor ph invention is not to beconsidered as limited to the fl tl l By way f illustration, tomene andspecific aromatic hydrocarbon reactants or to the ammonia may be broughttogether in sultable catalysts disclosed hereinafter or to themanipupmporuons and the mixture vwofized m a lations and conditions setforth in the examples. heating zone The vaporiud mixture than in- AB Wmbe apparent to those in the Sn, troduced into a reaction zone containinga catamums the type defined herein may be lyst ot the type definedhereinbefore. The reacused and a wide Variety other 01118- mm e may be alh' of any stumble type nitriles may be prepared by a suitablemodificauseiul in contact-catalytic operations; for exthe ammatichydmcll'bm ample, a catalyst bed contained in a shell, on a A reactormisting of sheu conmlnlng shell through which the catalyst flowsconcurcatalyst chamber heated by 8 B "may, or manual-currently. with thereactants. transfer medium thereover was used in each of the The "mm ofthe reactants are maintained m runs. The catalyst chamber contained thecatacontact with the catalyst at a predetermined eledescribed in ExampleAmmonib and vated temperature and or a predetermined pevarious aromatichydrocarbons were intro rind of time, both as set forth hereinbefore,and duced in the p r p e into he reactor for the resulting reactionmixture is passed through 60 minutes The reaction i u as passed acondensing zone into a receiving chamb R from the reactor, through acondenser, into a will be understood that when the catalyst flows firstreceiving chamber. Hydrogen and unconcurrently, o t fly, it t changedammonia were collected in a second reactants in a reaction chamber, thecatalyst will calving chamber and n eparated from each be thereaftersuitably separated from the reac- Otheh The nitriles and the unchangedfll y tion mixture by filtration, etc. The reaction mixaromatic ar ns rained in the first reture will be predominantly a mixture orbenzoceivins ch m r and r quently separated nitrile. hydrogen. unchangedtoluene, and unby distillation. The pertinent data and. the changedammonia. The benaonitrile and the unresults of each run are tabulated inthe following changed toluene will be condensed in passing table:

Tana:

$1 Liquid Moi Ratio o gl ii zr flts mph hrs more this; my.

mt carbon drocarbon Charge 4 Toluene... m Ki 7.3 9.0 Boo n rl 5 Xylens965 3.4 20 m9 Tolunitrlle.

through the condensing zone and will be retained in the receivingchamber. Benzonltrile can be It will be apparent that the presentinvention provides an eflicient, inexpensive and safe process forobtaining aromatic nitriles, particularly those of the benzene series.Our process is of considerable value in making available relativelyinexpensive aromatic nitriles which are useful, for example, asintermediates in organic synthesis.

This application is a continuation-in-part of copending application,Serial Number 539,034, filed June 6, 1944, now abandoned.

Although the present invention has been described in conjunction withpreferred embodiments, it is to be understood that modifications andvariations may be resorted to without departing from the spirit andscope of the invention, as those skilled in the art will readilyunderstand. Such variations and modifications are considered to bewithin the purview and scope of the appended claims.

We claim:

l. A process for the production of aromatic nitriles, which comprisescontacting an aromatic hydrocarbon having at least one nuclear hydrogenreplaced by a univalent, aliphatic, non-acetylenic hydrocarbon radical,and containing at least seven and up to eleven, inclusive, carbon atomsper molecule, with ammonia, in gaseous phase, at temperatures fallingwithin the range varying between about 850 F. and about 1250" F., in thepresence of catalytic oxides obtained by treatin a heteropoly compoundcontaining an acid anhydride molecule selected from the group consistingof Mps, W03, and V205, at a temperature and for a period of timesufllcient to decompose said heteropoly compound.

2. A process for the production of aromatic nitriles, which comprisescontacting an aromatic hydrocarbon having at least one nuclear hydrogenreplaced by a univalent, aliphatic, non-acetylenic hydrocarbon radical,and containing at least seven and up to eleven. inclusive, carbon atomsper nolecule, with ammonia, in gaseous phase, at temperatures fallingwithin the range varying uetween about 925 F. and about 1075" F., in thepresence of catalytic oxides obtained by treating a heteropoly compoundcontaining an acid aniydride molecule selected from the group consistingof M00:, W03. and V205, at a temperature falling within the rangevarying between about 900 F. and about 950 F. and for a period of timefalling within the range varying between about two hours and tenhours,'supported on a catalyst support.

3. A process for the production of aromatic nitriles, which comprisescontacting an aromatic hydrocarbon having at least one nuclear hydrogenreplaced by a univalent, aliphatic, nonacetylenic hydrocarbon radical,and containing at least seven and up to eleven, inclusive, carbon atomsper molecule, with ammonia. in gaseous phase, at temperatures fallingwithin the range varying between about 925 F. and about 1075 F., in thepresence of catalytic oxides obtained by treating a heteropoly compoundcontaining the acid anhydride molecule M003, at a temperature fallingwithin the range varying between about 300 F. and about 950 F. and for aperiod of time falling within the range varying between about two hoursand ten hours, supported on alumina.

4. A process for the production 01' aromatic nitriles, which comprisescontacting a methylsubstituted aromatic hydrocarbon containing at leastseven and up to eleven, inclusive, carbon atoms per molecule, withammonia, in gaseous phase, at temperatures falling within the rangevarying between about 850 F. and about 1250' F., in the presence ofcatalytic oxides obtained by 10 treating a heteropoly compoundcontaining the acid anhydride molecule M003, at a temperature and for aperiod of time suiiicient to decompose said heteropoly compound.

5. A process for the production oi aromatic nitriles, which comprisescontacting a methylsubstituted aromatic hydrocarbon containing at leastseven and up to eleven, inclusive, carbon atoms per molecule, withammonia, in gaseous phase, at temperatures falling within the rangevarying between about 925 F. and about 1075 F;, in the presence ofcatalytic oxides obtained by treating a heteropolycompound containingthe acid anhydride molecule M005, at a temperature falling within herange varying between about 300 F. and about 950 F. and for a period oftime falling within the range varying between about two hours and tenhours, supported on a catalyst support.

6. A process for the production of aromatic nitriles, which comprisescontacting a methylsubstituted aromatic hydrocarbon containing at leastseven and up to eleven, inclusive, carbon atoms per molecule, withammonia, in gaseous phase, at temperatures falling within the rangevarying between about 925 F. and about 1075 F., in the presence ofcatalytic oxides obtained by treating a heteropoly compound containingthe acid anhydride molecule M002, at a temperature falling within therange varying between about 300 F. and about 950 F. and for a period oitime falling within the range varying between about two hours and tenhours, supported on alumina.

'7. A process for the production of aromatic nitriles of the benzeneseries, which comprises contacting a methyl-substituted benzene withammonia, in gaseous phase, at temperatures i'alling within the rangevarying between about 050 F. and about 1250 F., in the presence ofcatalytic oxides obtained by treating a heteropoly compound containingthe acid anhydride molecule M003, at a temperature and for a period oftime suflicient to decompose said heteropoly compound.

8. A process for the production of aromatic nitriles of the benzeneseries, which comprises contacting a methyl-substituted benzene withammonia, in gaseous phase, at temperatures falling within the rangevarying between about 925 F. and about 1075' F., in the presence ofcatalytic oxides obtained by treating a heteropoiy compound containingthe acid anhydride molecule M003, at a temperature falling within therange varying between about 300 F. and about 950 F. and for a period 01'time falling within the'range varying between about two hours and tenhours, supported on a catalyst support.

9. A process for the production of aromatic nitriles of the benzeneseries, which comprises contacting a methyl-substituted benzene withammonia, in gaseous phase, at temperatures talling within the rangevarying between about 925 F. and about 1075 F., in the presence oicatalytic oxides obtained by treating a heteropoly compound containingthe acid anhydride molecule M001, at a temperature falling within therange varying between about 300 F. and about 950 F. and for a period oftime falling within the range varying between about two hours and tenhours, supported on alumina.

10. A process for the production of benzonitrile, which comprisescontacting toluene with ammonia, in gaseous phase, at temperaturesfalling within the range varying between about 925 F. and about l075 F.,in the presence of catalytic oxides obtained by treating a heteropolycombound containing the acid anhydride molecule MoOa. at a temperaturetailing within the range varying between about 300 F. and about 950 F.and for a period or time falling within the range varying between abouttwo hours and ten hours, supported on alumina.

11. A process for the production of aromatic hitrilesoi the benzeneseries, which comprises contacting a xylene with ammonia, in gaseousphase, at temperatures falling within therange varying between about 925F. and about 1075 F., in the presence of catalytic oxides obtained bytreating a heteropoly compound containing the acid anhydride moleculeM903. at a temperature falling within the range varying between about300 F. and about 950 F. and for a period or time 12 falling within therange varying between about two hours and ten hours, supported onalumina.

MILTON M MARISIG. WILLIAM I. BENTON. RICHARD B. BISHOP.

REFERENCES CITED The following references are of record in the 10 fileof this patent:

UNITED STATES PATENTS

